You’re three weeks into a training block for your spring marathon, and your knee starts niggling. Not agony. Just… there. You’ve got a long run on Sunday. Do you push through or pull the plug?
“Runner’s knee” isn’t one condition — it’s an umbrella term covering patellofemoral pain, IT band syndrome, and patellar tendinopathy. Each has different causes and different treatments, so getting the right diagnosis is the first step.
This is the question I hear most often from runners. And the answer isn’t always “stop running.” Sometimes knee pain is your body telling you to ease off slightly. Sometimes it’s a warning sign you’re about to make things much worse. The trick is knowing which is which.
I see a lot of runners — from Chester Greenway parkrunners to people training for Liverpool marathons — and most knee pain falls into one of three categories. Once you know which one you’ve got, the decision about whether to keep training becomes much clearer.
The Three Most Common Runner’s Knee Problems
Not all knee pain is created equal. The location, when it hurts, and what makes it worse all point to different underlying issues. Here are the three I see most often.
| Feature | Patellofemoral Pain | IT Band Syndrome | Patellar Tendinopathy |
|---|---|---|---|
| Pain location | Around/behind kneecap | Outer knee | Below kneecap |
| Worse with | Stairs, squatting, sitting | Downhill running, longer runs | Jumping, hill sprints |
| Key finding | Kneecap tracking issue | Tight lateral structures | Tendon load sensitivity |
| Main treatment | VMO strengthening, hip work | Foam rolling + hip strengthening | Progressive tendon loading |
Patellofemoral Pain (Runner's Knee)
Dull ache around or behind the kneecap. Usually worse going downhill, descending stairs, or after sitting for ages. Often a sign of poor hip control or quad weakness. This is the big one — probably 60% of the knee pain I see in runners.
IT Band Syndrome
Sharp pain on the outside of the knee, typically a few kilometres into a run. Gets worse with continued running. Hills and cambered surfaces are the usual culprits. Common in runners who ramp up mileage too quickly or do lots of trail running on uneven ground.
Patella Tendinopathy (Jumper's Knee)
Pain at the bottom of the kneecap, often a sharp, localised ache. Worse with explosive movements like hill sprints or speed work. Less common in pure distance runners, more typical if you're mixing in track sessions or plyometrics.
The key difference? Location and aggravating factors. Patellofemoral pain is vague and around the kneecap. IT band pain is sharp and lateral. Tendinopathy is specific and right on the tendon attachment. If you can pinpoint exactly where it hurts with one finger, you’re probably looking at IT band or tendinopathy. If it’s more of a generalised ache, it’s likely patellofemoral.
The Push Through or Stop Decision Framework
Here’s the truth: most runner’s knee pain isn’t structural damage. It’s not a torn ligament or meniscus. It’s a load management problem. Your tissues are being asked to do more than they’re currently capable of handling. That doesn’t mean you need to stop running entirely — it means you need to adjust the load.
I use a simple traffic light system with runners to help them make the call.
Green — Keep Running
Pain is mild (2-3 out of 10), settles within an hour of finishing your run, doesn't change your gait, and isn't getting worse week to week. You can keep training, but don't increase mileage or intensity right now. Monitor it closely.
Amber — Modify Your Training
Pain is moderate (4-6 out of 10), lingers for a few hours post-run, occasionally makes you adjust your stride, or some runs are noticeably worse than others. Time to back off. Drop your weekly mileage by 20-30%, cut out hills and speed work, and focus on easy-paced runs. This is the zone where most runners make the mistake of pushing on — don't.
Red — Stop and Get Help
Pain is severe (7+ out of 10), actively affects your running gait, gets worse during the run (not just after), or is progressively worsening run to run. Stop. Running through this will make it worse, and recovery time increases exponentially. Get an assessment — [book here](/services/initial-assessment) — and let's figure out what's actually going on before you dig yourself into a deeper hole.
The critical factor isn’t the pain level at the start of a run — it’s whether it’s increasing during the run and whether it’s getting worse between runs. If the answer to either of those questions is yes, you’re in amber or red territory.
Why Your Knee Hurts (And Why It’s Probably Not Your Knee)
I know that sounds contradictory, but hear me out. The knee is a hinge joint. It goes forwards and backwards. It doesn’t have much say in rotation or lateral movement — that’s controlled by your hips above and your ankles below. When your knee hurts, it’s usually because something else isn’t doing its job properly.
In my experience, about 80% of runner’s knee pain comes down to one or more of these training errors:
Too much, too soon. The classic. You’ve had a few good weeks, feel strong, bump your long run from 10k to 16k, and boom — knee pain. Your cardiovascular system adapts quickly. Your tendons and cartilage don’t. The rule of thumb is a 10% increase in weekly mileage, but honestly, even that’s aggressive if you’re coming back from a break.
Hill overload. Hills are brilliant for building strength, but they’re also a massive eccentric load on your quads and patella tendon. If you live somewhere like the Wirral coastal paths or regularly train around Delamere, you’re getting constant downhill loading. That adds up. If your knee pain started after adding hill sessions or trail runs, that’s your smoking gun.
Ignoring strength work. Running doesn’t make you strong enough to run. Sounds backwards, but it’s true. Your glutes and hip stabilisers control how your knee tracks when your foot hits the ground. If they’re weak, your knee collapses inward slightly on every step — thousands of times per run. Over time, that causes patellofemoral pain (Lauersen et al., 2014). I see this constantly in runners who only run and never do any targeted strength training.
Stand on one leg in front of a mirror. Slowly squat down to about 45 degrees and watch your knee. Does it dive inward past your big toe? That’s a sign of poor hip control. If your standing knee looks stable and tracks straight over your foot, your glutes are probably doing their job. If it wobbles all over the place, that’s where your work needs to be.
The solution isn’t complicated. Single-leg squats, clamshells, side-lying leg raises, and hip thrusts. Twice a week. You don’t need a gym. You don’t need fancy equipment. You just need to actually do it.
Running Shoes, Surfaces, and the Things That Matter Less Than You Think
Every runner with knee pain asks me about shoes. Should I get more cushioning? Do I need stability shoes? Is it because I’m a heel striker?
Here’s the reality: shoes matter, but they’re not the primary driver of knee pain. If you’re running in completely worn-out trainers or something wildly inappropriate for your foot type, yes, that can contribute. But most modern running shoes are pretty good, and swapping to a different model isn’t going to fix a load management or strength issue.
That said, if you’ve recently changed shoes and your knee pain started right after, that’s worth considering. And if your current shoes have 800+ kilometres on them, it’s probably time for a fresh pair regardless.
Surface matters a bit more. Concrete and tarmac are higher impact than trails or grass, but again — if you’re running sensible mileage with good strength work, your body should handle it. The issue is when you suddenly switch from mostly road running to lots of trail (or vice versa) without giving your tissues time to adapt.
The Wirral coastal paths are brilliant for low-impact running, but they’re uneven and cambered in places. If you’re doing all your miles on one side of the road or always running the same loop in the same direction, that constant lateral tilt can contribute to IT band issues. Mix it up. Run both directions. Vary your surfaces where you can.
A Basic Knee-Friendly Run Modification Strategy
If you’re in the amber zone — pain is there but manageable — here’s how to adjust your training without stopping entirely.
Cut your weekly mileage by 20-30%. If you’re running 40k a week, drop to 28-30k. Keep your runs frequent (better to run 5k four times a week than 20k once) but shorter.
Slow down. I mean really slow down. Conversational pace. If you can’t hold a full sentence without gasping, you’re going too hard. Slower running reduces ground reaction forces and gives your tissues a better chance to recover between sessions.
Avoid hills temporarily. Flat routes only for the next 2-3 weeks. The Chester Greenway is perfect for this — flat, predictable, and you can bail out easily if things flare up.
Add in walk breaks if needed. Run 8 minutes, walk 2 minutes. Repeat. There’s no shame in this. It reduces cumulative load and still maintains your aerobic fitness.
Start doing basic strength work immediately. Even if you’ve never done it before. Focus on glute activation and single-leg stability. This is the bit that actually fixes the underlying issue rather than just managing symptoms.
If you do this properly and your pain doesn’t improve within two weeks, it’s time for an assessment. You might need hands-on treatment, a more detailed loading plan, or imaging to rule out something structural. But most runners — genuinely, most — will see improvement with a sensible reduction in load and some targeted strength work.
When to Get Help
If you’re in the red zone, don’t wait. The longer you run on a progressively worsening knee, the longer your recovery time will be. I’ve seen runners push through for months and end up needing 12 weeks off. I’ve also seen runners come in early, adjust their training, get some hands-on treatment, and be back to full mileage within a month.
You should also get an assessment if:
- Your knee pain has been present for more than 3-4 weeks despite modifying your training
- You’ve had multiple episodes of the same knee pain
- The pain is sharp, sudden, or associated with swelling or instability
- You’ve got a race coming up and need a clear plan to get there safely
We run a lot of runners through here — people training for Chester marathons, Liverpool half marathons, parkrun PBs. The pattern is almost always the same: load exceeded capacity, strength work was absent or inconsistent, and the runner kept pushing because “it wasn’t that bad.” Until it was.
If that sounds familiar, book an initial assessment and let’s figure out what’s going on. We’ll look at your training history, assess your movement and strength, and give you a clear plan — not just to get rid of the pain, but to stop it coming back.
The Bottom Line
Knee pain doesn’t always mean stop running. But it does mean pay attention. Use the traffic light system. Be honest with yourself about whether your pain is stable, improving, or getting worse. And if you’re in doubt, err on the side of caution.
Most runner’s knee problems are fixable without stopping running entirely (Cook & Purdam, 2009). You just need to adjust the load, fix the strength gaps, and give your tissues time to adapt. The runners who do this early get back to full training quickly. The ones who ignore it and push through end up with chronic issues that take months to resolve.
Your call.
If you want more detail on specific knee conditions, check out our runner’s knee guide or the broader knee pain overview. And if you’re dealing with any other niggling injuries, the principles in our muscle strain guide and why strength training prevents injuries apply across the board.
